Method of expanding a railway tank car



Nov. 4, 1969 F. BROWN METHOD OF EXPANDING A RAILWAY TANK CAR Filed Aug. 1 1967- United States Patent O U.S. Cl. 29-412 5 Claims ABSTRACT OF THE DISCLOSURE A method of expanding a circular cylindrical tank car into a double truncated cylinder type car. A segment is cut from the bottom of the tank, combined with segments of a cylinder, and welded in place to form a central tank section having a double truncated cylinder configuration. Segments of a cylinder are then introduced to transition from the remaining cylindrical sections to the central section.

This invention relates in general to railway tank cars. It deals more particularly with a method of constructing a tank car.

A standard size tank car of the type presently being fabricated according to specification for bulk shippers of liquids and the like might be in the 20,000 gallon capacity category. Such cars meet the needs of the great majority of shippers. It has been learned from experience, however, that as the shipping volume of a shipper increases, economics dictate his acquisition and use of tank cars which are capable of transporting substantially greater loads. To meet this requirement, cars in the 30,000 to 50,000 gallon capacity Irange are also fabricated. These larger capacity cars include conventional cylindrical tank cars, elongated to increase their capacity, and cars of the double truncated cylinder type disclosed in the Schwartz, Jr., et al. Patent No. 3,277,842, assigned to the same assignee as the present invention.

New cars in the larger capacity range can, of course, be manufactured as new equipment for shippers when their needs dictate. However, the old, lower capacity cars, with their customized pipe and valve complexes, cooling and heating conduits, etc., cannot readily be used for other products by different shippers without extensive modification. The lower capacity cars thus become obsolete and an economic liability. This is obviously expensive.

Accordingly, it is an object of the present invention to provide a method of expanding existing railway tank cars to increase their capacity.

It is another object to provide a method of manufacturing a double truncated cylinder tank for a tank car from a conventional right circular cylindrical tank.

It is still another object to provide a method of expanding a tank car by manufacturing a double truncated cylinder tank in the aforedescribed manner and, concurrently, lengthening the tank.

It is yet another object to provide a method of the aforedescribed character which makes maximum use of tank segments from the original right circular cylindrical tank in construction of the double truncated cylinder tank.

It is a further object to provide a method of expanding a railway tank car to increase its capacity wherein expansion to the larger capacity tank requires a minimum of fabrication.

The foregoing and other objects are realized in accord with the method of the present invention by first providing a standard tank car incorporating a right circular cylindrical tank. A longitudinally elongated, substantially semi-cylindrical segment is cut out of the bottom of the tank. This substantially semi-cylindrical segment is 3,475,809 Patented Nov. 4, 1969 ICC trimmed down to a predetermined length less than the length of the cut-out. The trimmed substantially semicylindrical segment is welded along one side edge to a segment of a cylinder specially fabricated for this rela tionship. The composite substantially semi-cylindrical segment forms the major portion of a cylinder which corresponds identically in cross-sectional configuration to the original tank in the central area of the cut-out. The composite segment is then welded in side-edge-to-sideedge relationship with the original tank in the central area of the cut-out to form a central tank section comprised of opposed, truncated cylinders. Tie members are welded from one weld joint to the other inside the central tank section to strengthen the central tank section at these joints.

Outboard of each end of the cut-out in the tank, right circular cylindrical end tank sections remain. To form a transition section between each end of the central tank section and a corresponding end tank section, a distinctive transition segment of a cylinder is welded along its side edges to corresponding side edges in the cut-out and along its end edges to the corresponding end edges of the cut-out and the composite segment which forms a component ofthe central tank section.

In addition to expanding a right circular cylindrical tank into a double truncated cylinder tank, the invention also contemplates simultaneously lengthening the tank to additionally expand it, if additional expansion is desired. As such, after the cut-out has been made in the original tank, the tank is burned through on both sides of the center line of the tank car in planes perpendicular to the longitudinal axis of the tank. Substantially cylindrical expansion segments are then welded into the tank between the tank segments separated at the burn lines. The tank is thus lengthened. The central and transition tank sections are then completed in the aforedescribed manner.

The invention, together with its organization and method of operation, taken with other objects and advantages thereof, is illustrated more or less diagrammatically in the drawings, in which:

FIGURE 1 is a side elevational view of a double truncated cylinder tank car constructed according to the method of the present invention;

FIGURE 2 is a side elevational view of a right circular cylindrical tank, prior to its being expanded by the method of the present invention into a double truncated cylinder tank for the car illustrated in FIGURE l;

FIGURE 3 is a side elevational view of the right circular tank illustrated in FIGURE 2, after it has lbeen expanded lengthwise and its bottom section has been cut out according to the method of the invention; and

FIGURE 4 is a sectional view taken along line 4-4 of FIGURE l.

Referring now to the drawings, and particularly to FIGURE l, a railway tank car is illustrated generally at 10. The tank car 10 includes a tank 11 of the type illustrated in the Schwartz et al. patent hereinbefore referred to. The tank 11 is constructed by the method of the present invention and is mounted on generally conventional wheel trucks 12. The Wheel trucks 12 support the tank 11 on bolster assemblies 15.

The tank 11 includes oppositely disposed, right circular cylindrical end sections 20. The end sections 20 are capped in a conventional manner at 22. The tank 11 is supported by the wheel trucks l2 at the end sections 20.

At the center of the tank 11 is a central tank section 25 having a double truncated cylinder configuration in cross-section, as illustrated in FIGURE 4. The central tank section 2S is joined to each of the end tank sections 20 by a transition section 28. Each transition section 28 has the configuration of two opposed, segments of a cylinder intersecting at an angle to each other, and with their axes intersecting.

Referring now to FIGURE 2, to construct the tank 11 by the method of the invention, a tank car having a conventional right circular cylindrical tank T is provided. A longitudinally elongated segment 32 is cut out of the bottom of the tank T by conventional cutting techniques. The segment 32 is cut from the tank T so as to leave a cutout 35 in the tank bottom, and then cut down in a manner hereinafter described to a predetermined size and shape.

The cut-out 35 is dened by side edges 56 and end edges 57. The end edges 57 each describe a curve which lies in a plane inclined inwardly from the vertical at a slight angle. Each side edge 56 of the cut-out includes a straight center portion 56a, which is horizontal, and bracketing straight end portions 56b inclined upwardly from the horizontal at a slight angle.

The tank segment 32 which has been removed from the cut-out 35 is cut or trimmed down from its original size, as will be recognized. The side edges 61 of the segment 32 are trimmed straight to extend parallel to the side edge portions 56a of the cut-out 35. The end edges 62 of the segment 32 are then trimmed to the curve illustrated in dotted lines in FIGURE 2 so that they converge from one side edge y61a of the segment 32 to the opposite side edge 61b thereof, thus making the side edge 61b shorter than the side edge 61a. The signilicance of this relationship will be evident as the method of the invention is further described.

After the segment 32 has been trimmed to size and shape in the foregoing manner, the segmented tank T is further disassembled by being burned through along two lines 70 lying on opposite sides of the center line CL of the tank T. The burn lines 70 lie in vertical planes passing through those points on the side edges 56 of the cut-out 35 where the side edge portions 56a and 56b meet.

When the Itank T has been separated into two end segments 75 and a center segment 76 along the burn lines 70, cylindrical insert segments 80 of predetermined length, and corresponding in shape and radius of curvature to the tank segment 76, are introduced between the seg-ments 75, 76, in the manner illustrated in FIGURE 3, and welded in place. The tank T is thus elongated by the length of the insert segments 80. The cut-out 35 in the bottom of the tank T is also elongated by the length of the insert segments 80, the side edges 81 of which are co-extensive with corresponding side portions 56a of the cut-out 35.

With the tank T elongated in the manner described, another longitudinally elongated, substantially semi-cylindrical segment 85 is fabricated with a radius of curvature identical to the bottom cut-out segment 32. The new segment 85, which is seen in FIGURES l and 4, has side edges 85 and end edges 87. It is then welded along its longer, lower edge 86a to the longer side edge 61a of the segment 32. A composite tank segment 90 is the product of this joinder and the composite segment 90 has a crosssectional configuration identical to that of the combined tank segments 76 and 80.

The composite tank segment 90 is then welded to the tank segments 76 and 80 of the lengthened tank T to form the central section 25 of the expanded tank 11, as seen again in FIGURES l and 4. The side edges 61h and 86b of the composite tank seg-ment 90 are, as such, welded to corresponding side edges 81, 56a, of the assembled tank segments 76, 80. At this point, structural tie means in the form of a perforated metal plate 95 or the like is preferably welded between the horizontally extending weld joints so that it spans the interior of the tank 11 across the open faces of the truncated cylinders.

With the composite segment 90 welded in place in the aforedescribed manner to for-m the double truncated cylinder central tank section 25 of the tank 11, only the transition sections 28 of the tank remain to be completed. To such end a pair of identical transition tank segments 95, each identical in cross-sectional configuration, is fabricated. Since the configuration of each of these transition segments 95 is identical, together with their assembly into the tank 11, only one transition segment is discussed in detail. However, corresponding reference numerals are applied to each transition segment 95.

Each transition seg-ment 95 is a segment of a cylinder in conguration, with a radius of curvature equal to the radius of curvature of the composite segment 90 and the tank segments 75. The outer end edge 97 of the transition segment is cut to mate with the corresponding end edge 75 of the cut-out 35. The inner end edge 98 is cut to mate with the corresponding end edge 62, 87 of the composite segment 90. Similarly, the side edges 99 of the transition segment 95 are cut to mate properly with the side edge portions 56b of the cut-out 35. The angular relationship between the segment 95 and the weld joints formed by the juncture of these edges during welding is described in detail in the aforementioned Schwartz et al. patent. It is not specific to the method of the present invention.

A new and improved method of expanding a right circular cylindrical tank car has now been shown and described. By employing a tank segment cut from the bottom of the original cylindrical tank to form the major portion of the lower truncated cylinder in a double truncated cylinder tank, an expanded tank is fabricated at minimal cost.

The method of the invention also contemplates lengthening the original tank in its central section as it is expanded into a double truncated cylinder tank, all in the manner described. It should be recognized, however, that expansion into a double truncated cylinder tank might be accomplished without lengthening the tank. In such case, central insert segments would not be introduced into the tank and the composite segment would be shortened.

In the latter instance, where the composite segment 90 neednt be Ifabricated with the length of the insert segments 80 in min-d, the transition segments 95 can be formed from remaining segments of the cut-out 35 at opposite ends of the segment 32. These remaining segments must be built up along their edges to provide the necessary cylindrical expanse to complete the transition section, of course, but this is less expensive than fabricating new transition segments. Obviously, an even greater saving in cost is effected where the tank is not expanded by extending it through lengthening in the central section of the tank.

The tank car 10 has now been described as the product of an expansion method which may, but doesnt necessarily have to, lengthen the car as well as expand it into a double truncated cylinder tank car. In certain instances, expansion into the double truncated cylinder tank car is actually the second stage of a sequential expansion program over a period of years. The first stage of such expansion is preferably solely a lengthwise expansion by the method disclosed in the co-pending Kruizlenga application, Ser. No. 657,556, led: Aug. 1, 1967, and assigned to the same assignee as the present invention.

While the embodiment described herein is at present considered to be preferred, it is understood that various modifications and improvements may be made therein, and it is intended to cover in the appended claims al1 such modifications and improvements as fall within the true spirit and scope of the invention.

What is desired to be claimed and secured by Letters Patent of the United States is:

1. A method of expanding a railway tank car wherein the original car includes a right circular cylindrical tank, comprising the steps of: cutting a longitudinally elongated, substantially semi-cylindrical segment from the bottom of said tank so as to leave a cut-out in said bottom having longitudinally extending side edges, joining at least a longitudinal edge portion of said substantially semi-cylindrical segment to a supplemental segment of a cylinder to form a larger composite substantially semi-cylindrical segment, joining said composite substantially semi-cylindrical segment along its longitudinally extending edges to said longitudinally extending edges of said cut-out p0rtion of the tank, and joining each end of said composite substantially semi-cylindrical segment to a corresponding right circular cylindrical end section of said tank with transition segment means to form a double, truncated cylinder tank in the central section of said tank.

2. The method of claim 1 further characterized by and including the step of fabricating said composite substantially semi-cylindrical segment from the full width segment cut from said cut-out and said supplemental segment.

3. The method of claim 2 further characterized by and including the step of fabricating said composite substantially semi-cylindrical segment with a cross-sectional configuration substantially identical to the corresponding cross-sectional configuration of the truncated cylinder to which it is joined.

4. The method of claim 1 further characterized by and including forming the major portion of each of said transi- References Cited UNITED STATES PATENTS 1,350,830 8/1920 Murray et al. 29-411 2,304,354 12/1942 Harvey 29-401 2,715,377 8/1955 Gary 29-412 X 3,277,842 lO/l966 Schwartz et al 10S- 358 3,309,759 3/1967 Vittone 29-401 X 3,389,670 6/1968 Caple 29-416 X CHARLIE T. MOON, Primary Examiner U.S. C1. X.R. 

